A comparative analysis of predictive ability of three approaches to estimate the rate constants of reactions of H(2), H, H(2)O and CH(4) with electronically excited O(2)(a(1)Δ(g)) and O(2)(b(1)Σ(g)(+)) molecules is conducted. The first approach is based on a detailed ab initio study of potential energy surfaces. The second one is known as the "bond energy-bond order" method, and the third approach is a modification of the updated method of vibronic terms that makes it possible to evaluate the activation energy of reactions involving electronically excited species. The comparison showed that the estimates of the energy barrier by the updated method of vibronic terms for some reactions can be in good agreement with ab initio calculations and available experimental data. It was revealed that reactions of O(2)(b(1)Σ(g)(+)) molecules with H(2), H(2)O and CH(4) molecules and with the H atom result in the formation of electronically excited species. The reactivity of O(2)(b(1)Σ(g)(+)) molecules is smaller than that of O(2)(a(1)Δ(g)) ones, but much higher as compared to the reactivity of ground state O(2) molecules. For each reaction under study involving oxygen molecules in the excited electronic states O(2)(a(1)Δ(g)) and O(2)(b(1)Σ(g)(+)) the recommended temperature-dependent rate constants are presented.
The paper addresses detailed analysis of kinetic processes in the H
2
−O
2
, CO−O
2
and CH
4
−O
2
-reactive systems upon the presence of singlet oxygen molecules O
2
(
a
1
Δ
g
) and
and the influence of the activation of oxygen molecules in electric discharge on the acceleration of ignition in the H
2
−O
2
and CH
4
−O
2
mixtures. The possibility of the intensification of CO oxidation due to excitation of O
2
and N
2
molecule vibrations and generation of singlet oxygen molecules is also considered. It is shown that the effect of accelerating the ignition strongly depends on the reduced electric field and, as a consequence, on the composition of discharge plasma as well as on the features of chain mechanism development in oxy-fuel systems. It is revealed that the most effective approach for the intensification of CO oxidation both in the moist air and in the products of hydrocarbon combustion in air is the generation of O
2
(
a
1
Δ
g
) molecules by electric discharge. Computations showed that the presence of 1% O
2
(
a
1
Δ
g
) in the total oxygen allowed one to convert CO to CO
2
even at the temperature
T
=850–900 K in the time of 10
−2
s. The excitation of O
2
and N
2
molecule vibrations is less effective for such a conversion.
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